Inking device for rotary printing presses



' Patented June 12, 1934.

INKING DEVICE FOR ROTARY PRINTING PRESSES- George S. Rowell, Cleveland,Ohio, asslgnor to Multigraph Company, Wilmington, DeL, a corporation ofDelaware Application December 14, 1931, Serial No. 580,798

15 Claims. (01. 101-367) This invention is concerned with the inking ofrotary printing presses having segmentalprinting forms, and moreparticularly with planographic presses which employ an image-carryingplate mounted about a roller with the ends of the plate extending into agap in the roller, where the plate-securing and tensioningmeans are lo--cated. A roller is usually supplied for conveying the ink to the plate.If such inking roller is gear-driven, it is likely to produce ghostlines or other blemishes on the plate due to inaccurate engagement ofthe gears. On the other hand, if the inking roller is frictionallydriven, merely by contact with the plate, its speed of rotation 35 isreduced as the gap passes across the roller,

and this is liable to cause an unsatisfactory wiping action as therotating plate on the other side of the gap again engages the roller. Itis an object of my invention to avoid the objections abovenoted, andprovide for a continuous rotationof the inking rollers without requiringa gear drive or alarge number of coacting rollers. I accomplish thisresult in a simple manner by providing an arcuate member ormembersoccupying the space or spaces between the edges of the printing forms onthe roller and being of"substantially the same radius as the printingsurface, such arcuate member having asurface which may receive ink. Thisnot only causes the inking roller to continue its rotation without de-.celeration as it passes across the gap between the printing regions, butalso operates to redistribute ink to the roller, maintaining its surfaceevenly inked.

5 The arcuate member of myinvention, which has an ink-carrying surface,may perform only the function of maintaining the proper rotation'andinking action of the rollers which transfer the ink from a suitablesupply to the plate. If de-' sired, however, this gap-filling member mayitself supply ink to the inking rollers, and this is also a featureincluded within my invention.

My invention is hereinafter more fully explained in connection with thedrawings, illustrating different embodiments thereof, and the essentialnovel features are summarized in the claims. In the drawings:-

Fig. 1 is a sectional view through the platecarrying roller of aprinting machine equipped with one form of my invention adapted tosupply ink to the rollers; Fig. 2 is a longitudinal axial sectionthrough the roller of Fig. 1; Fig. 3 is an enlarged cross section in aplane parallel with Fig. 1 of the ink-carrying device itself; Fig. 4 isa fragmentary radial section through the ink carisa solid. arcuatemember.

rieri adjacent one end thereof; Fig. 5 is a fragmentary end view of theplate-carrying drum;

Fig. 6 is a detail of the clamping device for the ink carrier, on theplane indicated by the line 66 on Fig. 5; Fig. 7 is a perspective of asuitable bridge for the gap of the roller of Fig. 1, but which does not,of itself, supply the ink; Fig. 8 is a diagrammatic end view of aprinting roller carrying two printing plates and two ink distributingplates.

The printing roller of Figs. 1 and 2 comprises a" segmental portion 10mounted on, orformed with, end. discs 11 and 12, which aremounted on adriving shaft 15. The plate, designated 20, is shown as having one endprovided with holes hooking over pins 16 rigidly carried by the drumsegment. The other end of theplate has holes hooking over studs31 on alongitudinal portion of a suitable yoke 30 loosely mounted on the shaft15 and tensioned by one or more springs 32. As shown, the springs aresecured to a rod 17 mounted in the end members of the drum. This, orsome equivalent construction, serves to maintain the plate taut on thedrum surface 10; while the anchorages for the, ends of the plate areinside of the path of movement of thesurface of the plate.

In the gap of the cylinder 10,. between the anchorages 16 and 31 of theplate, I mount my bridge, which has an exterior surface substantiallycontinuing the cylindricalsurface of the 5 plate. In the constructionofFigs. 1 to 4, this bridge 40 is made hollow and may operate to continueink automatically fed to the rollers; while in the construction of Fig.'7, the bridge In either case, the arcuate surface .of the bridge isadapted to carry ink. I

Coacting with the plate 20 and with the bridge 40 or 90 area pairofink-transfer rollers 70, preferably of rubber, each of which coacts withanother roller '71 which, if desired, may be an ink-supply roller and beformed of such material as sponge-rubber, felt or otherfabric. Thedistance between the. two rollers 70, where they contact with thecylinder, is materially greater than the gap between the edge of thebridge and the plate 20 so that, in the rotation of the drum, one rolleror the other is always in contact with either the plate or the bridge. 1Thus, when. either 105 .roller passes the short gap between the plateengagement with the roller 70 continues to drive such lateral roller 70at undiminished speed.

It results from the described arrangement that, while my rollers arefrictionally driven, they are maintained at a constant speed and serveto ink the plate effectively so that the same may properly coact eitherwith a transfer blanket or directly against the paper held by a suitableplaten. The member in Fig. 1 is intended to indicate either a transferroller or a platen roller, according to whether the printing is effectedin the offset manner or directly.

I will first describe the ink-feeding form of my bridge illustrated inFigs. 1 to 4, inclusive. In these figures, the bridge 40 comprises afabric covering mounted on the perforated arcuate sheet of metal 41.This sheet of metal is supported by a rectangular metal frame 42, theparallel sides of which are shown as flanged outwardly at 43 and securedto the arcuate plate in a suitable manner, as by screws or rivets. Theend members 44 of the supporting frame are also parallel to each other.Within the rectangular box just provided is a movable bottom 50, theupper surface of which is preferably curved concentrically with thebridge plate 41, and the side and end edges of which carry a rubberwiper 51 which engages the side walls and end walls of the box 42. Thisbottom 50 is spring-pressed toward the top 41 of the box 42.

I have shown the bottom as provided with four downwardly extending pins53 and 54. The pins 53 extend slidably through the longitudinal rod 1'7of thedrum heretofore mentioned; while the pins 54 extend slidablythrough a similar longitudinal rod 18 of the drum. Suitable springs 55,surrounding the rods 53 or 54 between the frame rods and the movablebottom 50, tend to press the bottom toward the top plate 41.

Means are provided for the insertion of a supply of ink into the spacewithin the box 42 between the movable bottom and the top plate. In Fig.4, I have indicated at 60 a passageway from the ink space through one ofthe end walls 44 into a valve cavity 61. From this cavity, a passageway62 leads to an opening in a boss 63 formed on the end plate 44. Thisopening is normally closed by a screw plug 64, and the connectionbetween the cavity 62 and the cavity 61 is normally closed by a checkvalve, indicated by a ball 65 pressed down by a spring 66 seated againsta removable plug 67.

Removal of the plug 64 allows ink to be forced into the cavity 62 andbeyond the check valve and through the passageway 60 into the spaceabove the movable bottom 50. Pressure on such ink will force down thebottom against the action of the springs 55, and then, in use, thesesprings, reacting, press the bottom upwardly and force the ink throughthe perforations of the crown plate 41 and through the fabric surface 40so that that surface is maintained inked.

To enable the ink to be readily supplied to the ink carrier justdescribed, I form an opening 19 in the end member 12 of the drum, whichopening stands opposite the plug 64. When that plug is removed, I mayscrew into the threads which it had occupied the tip of a flexible tubeA adapted to contain ink. By squeezing this tube in the usual manner,the plastic ink is forced into the cavity 62 and beyond the check valve65 through the passageway 60 into the space in the hollow bridge. Whenthe pressure on the tube is' released, the check valve 65 preventsescape of the ink from the hollow bridge, and a proper manipulation ofthe tube may draw back into it ink from the cavity 62 so that there isno ink escape as the tube is unscrewed from the cavity. The returnedplug 64 insures against any leakage of ink from the opening during theoperation of the machine.

To position the hollow bridge described accurately in the gap of thedrum, I provide abutment screws 80, which are adjustably mounted inbosses 81 carried by the hubs of the end members 11 and 12. By turningthese screws and locking them by their jam nuts, the position of thehollow bridge may be accurately selected; then the bridge is locked inplace by cap screws 85 which pass through slots 86 in the end members ofthe drum into bosses 87 formed on the end walls of the bridge. Thisoperation is illustrated in Figs.5 and 6.

While there are advantages in supplying ink to the bridge 40 so that theinking rollers may be automatically supplied; the other effect of thebridge maintaining the rollers constantly rotating may be obtained bythe solid metal bridge of Fig. 7. This bridge comprises the arcuateplate 90 supported by end walls 91. These walls are shown as flangedinwardly at their bottoms as at 92 to abut the pins heretoforementioned, which limit the innermost position of the bridge. The endwalls are provided with outwardly extending bosses 94, which areinternally threaded to receive the cap screws extending through the drumends as already explained. Accordingly, this simple metal bridge may bemaintained in the gap of the plate-carrying roller in the same positionas the ink-supplying bridge already described; in fact, isinterchangeable with it.

Figure 8 is a diagrammatic illustration of an embodiment employing twoink distributing plates and 90 having a surface similar to the bridge 90of Fig. '7, and operating between two printing plates 20% and 20*. Insuch an arrangement, after the inking of each plate, the ink on therollers is smoothed and ironed out by engagement of a distributingplate.

When the all-metal bridge of Fig. 7 or Fig. 8 is employed, it isdesirable thatthe metal surface thereof be of such form that it maycarry ink. Ordinarily smooth metal will not so act with certain types ofink; but a grained surface similar to a grained lithographic plate willcarry most inks, or a surface treated with a proper enamel is effectivefor this purpose. Such a grained or enameled surface allows theemployment of a supply roller '71 of the type which eliminates an inkfountain and permits the use of an ink of a rather heavy body.

By providing an ink-receptive surface, in any of the embodiments of myinvention, it results that after the surface is inked, it acts on therollers to redistribute ink thereto, and in effect to smooth or iron outthe ink on the roller, preventing irregularities in the coat of ink,which might cause ghost lines" on the print.

It will be understood that the transfer cylinder with its blanket or theplaten, as the case may be, will be of the same size as the printingcylinder with its plate or plates, and will be provided with a similargap or gaps so that there will be no possibility of the ink from thebridge passing directly to the transfer blanket or paper.

My bridge, whether of the ink-supplying form or of the solid metal-plateform, is simple in construction; and is readily mounted in the drum inaccurate position to coact with the inking rollers. The bridge may alsobe readily removed for cleaning, or if the removal is desired for moreconveniently changing the printing plate. If the ink-supplying form ofbridge is used, the ink tube may be very quickly attached to it, and theink fed to the hollow bridge, without disturbing the bridge or the plateon the drum.

I claim:

1. The combination of a roller having a gap, a printing surface adaptedto be carried by the roller, a bridge carried by the roller at the gap,means for radially adjusting the position of the bridge, two inkingrollers each adapted to engage the printing surface and the bridge, saidrollers being spaced farther apart than the distance between the edge ofthe bridge and the printing surface, and means for communicating motionfrom one roller to the other.

2. In the combination of a drum having a gap, means for securing aplanographic printing plate about the same, an arcuate bridge located inthe gap, and means for adjustably holding the bridge in position so thatits exterior surface may form a portion of substantially the sametheoretic cylinder as that bounding the printing surface of the plate.

3. The combination of a roller adapted to carry an arcuate printingsurface, and having a gap, a hollow container located within said gapand having passageways from its interior to its exterior, whereby inksupplied to the interior may pass to the exterior, and an ink-transferroller adapted to engage successively the printing surface and thesurface of the ink device.

4. In the combination of a drum having a gap, means for securing aprinting surface on the drum, a hollow container carried by the drumwithin said gap and having an arcuate surface connected by passagewayswith the interior of the container, means for forcing ink from thecontainer to said arcuate surface, and means for transferring ink fromsaid arcuate surface to the printing surface.

5. The combination of a drum having a gap, means for securing a printingsurface on the drum, a hollow container located in the gap, saidcontainer having a perforated arcuate top, a movable bottom in thecontainer spring-pressed toward the top, and means for transferring inkfrom the top of said container to the printing surface.

6. The combination of a drum having a gap, means for holding a printingsurface thereon, a hollow container located in the gap and having aperforated arcuate surface surmounted by a fabric surface, a movablebottom in the container, maintaining an ink-tight connection with thecontainer walls, means for pressing said bottom toward the top, meansfor supplying ink to the interior of the container, and a plurality ofmutually connected inking rollers adapted to engage the printing surfaceand the fabric surface, two such rollers being located such distanceapart that when one of them is at the space between the edge of the topand the printing surface the other is engaging either the printingsurface or such top.

7. The combination of a movable printing member, means for securingthereon a printing plate and a non-printing plate having an inkretainingsurface, the printing plate and nonprinting plate being at the sameradial distance and traveling in the same path as the member moves, andan inking roller adapted to coact successively with the printing andnon-printing plates, and an ink-supply roller coacting with the inkingroller and adapted to deliver ink thereto.

8. The combination of a printing drum, having a gap, means for securinga printing plate thereon, a: bridge located in the gap, and having anarcuate surface carried by two radial end portions and means forsecuring the radial end portions to the drum.

9. The combination of means adapted to carry a printing surface andhaving a gap, a member located in said gap and having an internal inkcarrier and having an exposed exterior surface, and a roller which maycoact successively with the printing surface and ink-supply surface.

10. In the combination with a movable member for carrying a printingsurface, of a hollow ink-supply device carried by said member, meanswhereby ink may pass from the interior of said device to the exterior,and an inking roller adapted to engage successively the printing surfaceand the inking device due to the movement of said movable member.

11. In the combination of a movable member carrying a printing surface,a hollow container mounted on said member and having a perforated top, afabric covering over said top, and means for transferring ink from thefabric to the printing surface.

12. In a printing machine, the combination of a roller, a plurality ofsegmental printing plates thereon, ink distributing plates located onthe roller between the printing plates and at the same radial distance,and an inking system having a form roller the axis of which does notmove during operation, said form roller being adapted to coactalternately with the printing plates and the ink distributing plates.

13. A drum adapted to carry a printing surface, an ink container locatedwithin the drum, means to force ink from the container to the exteriorof the drum, and an inking roller adapted to pick up such ink and engagethe printing surface.

14. The combination of a drum adapted to carry an arcuate printingsurface and having a gap, a hollow container located within the drum andhaving an arcuate top at the gap, means in the container adapted topress ink therein to said arcuate top, and an inking roller adapted toengage with the arcuate top and the printing surface.

15. In a printing machine, the combination of a form-carrying drumhaving a gap, an ink-supply device in the gap comprising a hollowcontainer having a perforated top with a fabric covering held over theperforations and exposed at the periphery of the drum, a movable bottomin the container, springs for. pressing the bottom toward the top, andpacking at the edges of the bottom for maintaining a close engagementbetween the bottom and the container walls.

GEORGE S. ROWELL.

